1 definition by Wikipedia83
Dirty Sánchez describes the practice, in which the active partner, immediately following ejaculation, inserts the finger into the anus of the passive partner and then smears a mixture of semen and feces under the nose of the passive partner. Eventually, the finger is then licked off by both partners. The naming was chosen, because this was to evoke the impression of a "Mexican moustache."
by Wikipedia83 October 3, 2006